Large machines called pulverizers/classifiers are used to crush and pulverize lump coal into powdered fines for injection into a combustion chamber where heat is generated to turn water into steam in coal-fired utility plants. Several types of commercial pulverizer/classifier machines are available in the commercial market, one of which is shown for illustration purposes in FIGS. 1 through 3 of this application. As shown in FIGS. 1-3, the OEM classifier multiport outlet structure is installed in a circular opening 14 in the top of the inverted-bottle-shaped upper housing 16 of the classifier 10. The OEM structure comprises a cylindrical skirt 72 concentric with the opening 14 and extending down into the classifier housing in surrounding, spaced relationship with the coal inlet chute 12.
Mounted concentrically with and partially inside of the skirt 72 is a Venturi 70 comprising a diverging lower cone 74 integral with a converging upper cone 76. The cone 76 is joined to the skirt 72 by angled radial vanes 78 and the lower cone 74 is secured to the chute 12 by welding or other known means.
On top of the Venturi 70 is an outlet structure comprising a heavy steel circular plate 82 with spaced bolt holes. Cut into the plate are four kidney-shaped outlet holes. Cast steel tubes 84, 86, 88 and 90 sit on and over these holes. The bottoms of the tubes 84, 86, 88 are kidney-shaped to match the holes in plate 82. Flanges 92, 94, 96 and 98 are integral with the tubes 84, 86, 88 and 90 respectively and have bolt holes drilled in them for mounting purposes.
The bodies of tubes 84, 86, 88 and 90 change shape vertically from a kidney-shape near the bottom to a circular shape near the top flanges 100, 102, 104 and 106. Those flanges are provided with bolt holes for attachment to coal conduits 46, 48, 50 and 52 shown in FIG. 3 as part of a system modified to receive the present invention as hereinafter described.